Air-Conditioning, Heating, and Refrigeration

Institute (AHRI) Low-GWP Alternative Refrigerants

Evaluation Program (Low-GWP AREP)

TEST REPORT #8

System Drop-In Tests of R-134a, 

R-1234yf, OpteonTM XP10, R-1234ze(E), 

and N13a in a Commercial Bottle 

Cooler/Freezer

Doron Shapiro

Hussmann Corporation

12999 St. Charles Rock Rd.

Bridgeton, MO 63044, USA

January 25, 2013

This report has been made available to the public

as part of the author company’s participation in the 

AHRI’s Low-GWP AREP.

The tests in this report were conducted prior to the 

Low-GWP AREP, and may not exactly meet the 

program’s requirements. The results were reviewed 

and accepted as they are useful and informative. 
List of Tested Refrigerants’ Compositions (Mass%)

R-1234yf R-1234yf (100)

N-13a R-134a/R-1234yf/R-1234ze(E) (42/18/40)

R-1234ze(E) R-1234ze(E) (100)

OpteonTM XP10 R-134a/R-1234yf (44/56)
Page 2

1. Introduction:

From October 2010 through May 2011, Hussmann completed R-134a baseline testing and

system drop-in testing of R-1234yf, OpteonTM XP10, R-1234ze(E), and N13a in a commercial 

bottle cooler/freezer. Figure 1 shows available bottle coolers in this product line.

Fig 1. Bottle coolers (center unit, Model ARV-570, was tested)

It is important to note that the results reported here were completed prior to the start of the AREP 

work. Nevertheless, Hussmann wishes to present the results, since they are relevant and useful 

as part of the overall refrigerant evaluation program. It must be understood that because the 

Hussmann tests were completed before the AREP work had started, parts of the test setup, 

conditions, and procedures may be different than specified in the AREP Participants Handbook.

2. Details of Test Setup:

a. Description of System

Figure 2 shows a photo of the test unit. As shown, the unit had a single door, approximately 1.8 

m (6 ft) tall. One important difference between this unit and typical bottle coolers is that the test 

unit can operate below freezing, with a -5.6°C (22°F) setpoint. The unit is intended to be used 

with beer cans or bottles, and the -5.6°C setpoint is not quite cold enough to freeze beer. 

However, due to condensation, a layer of ice forms on a beer can when it is removed from the 

unit. 
Page 3

Fig 2. Model ARV-570 used for drop-in tests

Note discharge air temperature display in upper right reads 23°F (-5°C) 

The evaporator and evaporator fan are located in the top-back of these coolers. The compressor, 

condenser, and condenser fan are located in the bottom. Other details are:

• Compressor: Fractional horsepower, hermetic, reciprocating type, 10.61 cm^3 displacement

• Nominal motor size: 270 W

• Condenser: Approximately 30 cm width x 28 cm height 3.3 cm depth, with 16 tubes total in 

an 8 x 2 staggered pattern with copper tubes and aluminum fins, 3.1 fins/cm 

• Expansion device: Capillary tube 244 cm length with 1.24 mm ID. The capillary tube is 

piped through the suction tube, thus providing a liquid-to-suction heat exchanger.

• Evaporator: Approximately 49 cm width x 18 cm height x 7 cm depth, with 21 tubes total in 

a 7 x 3 staggered pattern with copper tubes and aluminum fins, 2.4 fins/cm
Page 4

b. Description of Modifications to System

The normal refrigerant charge for these units is 266 g of R-134a. However, the additional charge 

needed to accommodate the refrigerant flow meter and connecting piping was calculated and 

included in the tests. Thus, 322 g of refrigerant was used for the tests. A refrigerant mass flow 

meter was installed in the compressor discharge line. 

c. Description of Tests Conducted

Two types of tests were conducted: 1) “Steady-state” tests with door opening/closing cycles in 

accordance with ASHRAE Standard 72-2005, Method of Testing Commercial Refrigerators and 

Freezers and 2) full pull-down and half pull-down tests in accordance with a soft-drink bottler’s 

specifications.

A detailed discussion of these two types of tests is beyond the scope of this report, but in short, 

the ASHRAE tests measured performance over a normal operating cycle including automated 

door openings and defrost period. The full pull-down test measured performance with the full 

product load “soaked” at 32°C (90°F). Similarly, the half pull-down test measured performance 

with half the product load soaked at 32°C.

The main objectives of the evaluation were:

a) Conduct performance tests in accordance with ASHRAE Standard No. 72-2005

• Two bottle cooler thermostat settings were tested, -5.6°C (22°F) and 3.3°C (38°F).

• Two test cell ambient conditions were tested, 23.9°C (75°F)/55% relative humidity 

and 26.7°C (80°F)/55% relative humidity.

b) Conduct full pull-down and half pull-down tests in accordance with a soft-drink bottler’s 

specifications

c) Compare performance values such as discharge air temperatures, product simulator 

temperatures, suction pressure, discharge pressure, compressor mass flow, and 

compressor input power 

d) Repeat each series of tests with the refrigerants listed in Table 1

e) Note any other important observations

An overview of the tests conditions is shown in Table 1, and Figure 3 shows a flow diagram of 

the refrigerant circuit.
Page 5

Table 1: Overview of test conditions and refrigerants

Refrigerants:

R-134a

R-1234yf

OpteonTM XP10

R-1234ze(E)

N13a

Test type: ASHRAE 72

Full

PullDown

Half 

PullDown

Test cell temperature °C 

(°F):

23.9 

(75)

23.9 

(75)

26.7

(80)

26.7

(80)

32.2

(90)

32.2

(90)

Test cell relative 

humidity: 55% 55% 55% 55% 65% 65%

Bottle cooler setpoint, °C 

(°F):

5.6 

(38)

-3.3 

(22)

5.6 

(38)

-3.3 

(22)

5.6 

(38)

5.6 

(38)

Fig 3. Flow diagram of refrigerant circuit

Tests were conducted in Test Cell No. 11 at the Hussmann R&D Lab in Bridgeton, MO, USA.

The following data were recorded:

• Compressor suction and discharge pressures 

• Refrigerant mass flow rate 

• Refrigerant pressure drops through evaporator, condenser, and refrigerant flow meter

• Compressor suction and discharge temperatures

Condenser

Evaporator

Compressor

Filter

Dryer

Flow

Meter

Capillary tube

run through

suction line

Capillary 

tube
Page 6

• Evaporator refrigerant outlet temperature

• Condenser air inlet and outlet temperatures

• Condenser refrigerant inlet and outlet temperatures

• Discharge air temperatures, 5 cm from left end, center, and 5 cm from right end of discharge 

air duct

• Return air temperatures, 5 cm from left end, center, and 5 cm from right end of return air 

duct

• Test cell ambient dry and wet bulb temperatures

• Test unit voltage, current, and power

• Compressor current and power

• Evaporator fan power (checked once, not recorded continuously)

A PC-based Data Acquisition System was used to record measurements. Temperatures were 

recorded every 60 seconds. Power, pressure, and differential pressure values were recorded 

every 10 seconds. Data was summarized in spreadsheets in accordance with the corresponding 

test standard. Refrigerant properties were obtained using REFPROP Database 23, Version 8.0

3. Results

Table 2

Low GWP AREP system drop-in test data form

Manufacturer: Hussmann Corporation Manufacturer’s Notation: ARV-570 

 

Basic Information

Alternative Refrigerants (If not proprietary, composition as 

Charged, % wt)

Please refer to Table 1

Baseline Refrigerant and Lubricant R-134a/POE

Make and Model of System Hussmann ARV-570

Nominal Capacity W 350

Mode Cooling

Compressor Type Hermetic Reciprocating

Compressor Displacement cm^3 10.61

Nominal motor speed, rpm Approx. 3500

Actual motor speed Not Measured

Expansion Device Type Capillary Tube

Lubricant type POE, ISO10

Refrigerant composition at compressor inlet Please refer to Table 1

Note: The above basic information is the same for all tests, and therefore is included here only.
Page 7

3.1 ASHRAE 72 Tests

Tables 3 through 6 show averaged data over the duration of each test run. To make it easier to 

review the tables, each row has a number value and each column has a Test ID number. 

Table 3 shows results at 23.9°C/55% relative humidity ambient conditions with the 3.3°C bottler 

cooler setpoint. Beginning with the left side of Table 3, three sets of baseline tests were 

conducted, Test ID Nos. 1, 2 and 3. Note the completion dates were 10/12/10, 2/16/11, and 

5/09/11. These tests were conducted with R134a at the beginning, middle, and end of the overall 

program to verify that the baseline performance was repeatable. For example, if something had 

gone wrong with the compressor or instrumentation, large changes would likely have been seen

between these three tests. 

As shown in Table 3, there were some modest differences among the three baseline 

measurements. For example, in Rows 11 and 12, the compressor mass flow dropped slightly 

from 6.37 kg/hr to 6.24 kg/hr and then further to 6.16 kg/hr, for Tests 1, 2, and 3, respectively. 

Thus, the mass flow was 3.4% lower in Test 3 versus Test 1. On the other hand, there was 

almost no difference in the compressor power (Row 66) for these three tests, with 116 W, 118 W

and again 118 W for Tests 1, 2, and 3, respectively. One possible cause of these changes is 

slightly different refrigerant charge. Beginning in 2011, an improved scale was used to charge 

the system. The new scale had +/-1 gram (+/-0.036 ounce) precision versus the old scale, which 

had +/- 7 gram (+/- 0.25 ounce) precision. 

Keeping in mind the three sets of baseline results, some main results in Table 3 are:

• Rows 9 and 10: The suction and discharge pressure, 205 kPa and 558 kPa, respectively of 

R-1234ze(E) were considerably lower than the other refrigerants. 

• Row 11 and 12: The mass flow rate of R-1234yf (Test 4) was 13.9% higher than the first 

baseline test (Test 1).

• Rows 23 through 25: The discharge air temperatures were nearly identical for all tests. We 

would expect this result since discharge air temperature was the basis for cycling the 

compressor on/off.

• Rows 66 and 67: The compressor power was within +/- 2.7% for all tests.

• Rows 69 and 70: The compressor run time for R-1234ze(E) (Test 6) was 21.5% higher than 

the first baseline test.

• Rows 79 and 80: The average cooling capacity for R-1234yf, XP10, R-1234ze, and N13a 

were 8.5%, 7.8%, 7.9%, and 5.2% lower, respectively

• Rows 80.1 and 80.2: The average COP for R-1234yf, XP10, R-1234ze, and N13a were 

10.9%, 9.7%, 5.7%, and again 5.7% lower, respectively
Page 8

Table 3

Results at 23.9°C (75°F)/55% relative humidity ambient conditions,

3.3°C (38°F) bottle cooler set point

Row 0 Refrigerant

1 Test type

2 Test ID no.

4 Test cell temperature setpoint db °C 23.9 23.9 23.9 23.9 23.9 23.9 23.9

4.1 Test cell temperature setpoint wb °C 17.8 17.8 17.8 17.8 17.8 17.8 17.8

5 Test cell relative humidity setpoint, %

6 Bottle cooler setpoint °C 3.3 3.3 3.3 3.3 3.3 3.3 3.3

8 Completion date

9 Suction pressure kPa 285 283 279 303 305 205 264

10 Discharge pressure kPa 702 704 704 730 727 558 674

11 Refrigerant flow rate kg/hr 6.37 6.24 6.16 7.26 6.58 6.50 6.53

12 Difference %

13 Refrigerant pressure drop evaporator kPa 1.39 1.83 1.67 1.36 1.70 2.97 2.90

14 Refrigerant pressure drop condenser kPa 1.43 1.53 1.43 1.53 1.58 1.21 1.50

15 Refrigerant pressure drop flow meter kPa 26.78 27.33 27.89 26.76 27.01 29.89 28.46

16 Compressor suction temperature °C 19.4 20.2 20.4 20.1 21.0 18.2 20.4

17 Compressor discharge temperature °C 40.0 40.9 41.3 41.3 40.9 40.0 41.6

18 Evaporator outlet temperature °C -0.2 0.7 1.0 1.3 1.9 0.0 0.9

19 Condenser air inlet temperature °C 23.9 24.0 24.2 24.1 24.2 24.0 24.4

20 Condenser air outlet temperature °C 25.8 26.0 26.2 26.0 26.1 25.7 26.3

21 Condenser refrigerant inlet temperature °C 32.1 31.9 32.2 32.8 32.9 32.0 32.8

22 Condenser refrigerant outlet temp °C 27.7 27.6 27.8 27.7 27.9 27.6 28.0

23 Refrigerated air discharge temperature 5 cm from left wall °C 2.5 2.5 2.5 2.4 2.5 2.5 2.4

24 Refrigerated air discharge temperature center °C 2.6 2.6 2.6 2.6 2.7 2.6 2.6

25 Refrigerated air dischrage temperature 5 cm from right wall °C 2.4 2.4 2.3 2.4 2.5 2.4 2.4

26 Refrigerated air return temperature 5 cm from left wall °C 3.8 3.9 3.9 3.8 3.9 3.8 3.8

27 Refrigerated air return temperature center °C 4.1 4.2 4.1 4.1 4.2 4.2 4.2

28 Refrigerated air return temperature 5 cm from right wall °C 4.1 4.3 4.3 4.2 4.3 4.3 4.3

29 Test cell dry bulb (1 of 2) °C 23.9 23.9 23.8 24.0 24.1 23.9 24.2

30 Test cell dry bulb (2 of 2) °C 23.4 23.6 23.5 23.7 23.8 23.7 24.0

31 Test cell wet bulb °C 17.6 18.1 18.2 18.1 18.3 17.8 18.2

40 Test cell relative humidity %

50 Product simulator temperatures

51 Integrated average product simulator temperature °C 4.0 4.0 4.1 4.0 4.0 4.0 4.1

52 {CTS} Integrated coldest product simulator. temperature °C 3.4 3.4 3.4 3.3 3.1 3.4 3.4

54 {WTS} Integrated warmest product simulator temperature °C 4.4 4.6 4.5 4.5 4.6 4.5 4.6

59 Refrigerant charge g 322+/-7 322 +/-1 322 +/-1 322+/-7 322 +/-1 322 +/-1 322 +/-1

61 Supply voltage

66 Compressor power W

67 Difference %

69 Compressor run time, %

70 Difference %

71 Evaporator fan power W (checked once, not recorded 

continuously)

73 Evaporating temperature (avg. of dew and bubble ) °C -0.8 -0.9 -1.3 -0.9 -1.5 -1.3 -1.8

74 Condensing temperature (avg. of dew and bubble) °C 26.8 26.9 26.9 27.9 27.8 28.8 27.2

75 Superheat at compressor inlet °K 20.1 21.1 21.7 21.0 22.5 19.4 22.2

79 Average cooling capacity W* 317 311 307 290 292 292 301

80 Difference %

80.1 Average COP (W/W) 2.72 2.64 2.60 2.43 2.46 2.57 2.57

80.2 Difference % 0.0% -3.0% -4.3% -10.9% -9.7% -5.7% -5.7%

*Assumes saturated liquid at inlet of expansion device

118 120 121 120 122 121 120

117

0.6%

-0.2%

35.0% 35.0%

-0.2% 21.5%

42.6% 37.0%

5.5%

-2.3%

116 114

0% 2.7%

120 119

2.1%

2.4%

35.9%

1.3%

118

35.1%

0%

118

1.1%

35.1%

0.0%

54.5% 57.4% 58.1% 56.1% 57.6% 55.0% 55.6%

0% -2.1% -3.4% 13.9% 3.3% 2.0% 2.5%

R-1234ze N13a

6 7

03/01/11 03/27/11

55 55

ASHRAE ASHRAE ASHRAE ASHRAE

11/28/10 01/11/11

R-1234yf OpteonTM 

XP10

55 55

2 5

55

R134a R134a

10/12/10 02/16/11 05/09/11

R134a

ASHRAE ASHRAE 

(repeat)

55 55

ASHRAE 

(repeat)

1 3 4

58 58 58 58 58 58 58

0% -1.9% -3.0% -8.5% -7.8% -7.9% -5.2%
Page 9

Table 4 shows results at 23.9°C/55% relative humidity ambient conditions with the -5.6°C bottle 

cooler setpoint. Some main results in this table are:

• Rows 9 and 10: The suction and discharge pressures, 132 kPa and 592 kPa, respectively of 

R-1234ze(E) (Test 11) were considerably lower than the other refrigerants. 

• Rows 11 and 12: The mass flow rate of R-1234yf (Test 9) was 19.6% higher than the 

baseline.

• Rows 23 through 25: The discharge air temperatures were nearly identical for all tests. 

Again, we would expect this result since discharge air temperature was the basis for cycling 

the compressor on/off.

• Rows 66 and 67: Compared to the baseline, the compressor power values were 8.0% higher, 

6.5% higher, 4.4% lower, and 1.4% higher for R-1234yf, XP10, R-1234ze(E), and N13a, 

respectively. 

• Rows 69 and 70: The compressor run time for R-1234ze(E) (Test 11) was 18.1% higher than 

the baseline.

• Rows 79 and 80: The average cooling capacity for R-1234yf, R-1234ze, and N13a were 

5.5%, 14.3%, and 6.5% lower, respectively

• Rows 80.1 and 80.2: The average COP for R-1234yf, XP10, R-1234ze, and N13a were 

12.5%, 9.5%, 10.3%, and 7.8% lower, respectively

Table 5 shows results at 26.7°C/55% relative humidity ambient conditions with the 3.3°C bottle 

cooler setpoint. Some main results in this table are:

• Rows 9 and 10: The suction and discharge pressures, 201 kPa and 612 kPa, respectively of 

R-1234ze(E) (Test 16) were considerably lower than the other refrigerants. 

• Rows 11 and 12: The mass flow rate of R-1234yf (Test 14) was 14.8% higher than the 

baseline.

• Rows 23 through 25: As with the other test conditions, the discharge air temperatures were 

nearly identical for all tests. 

• Rows 66 and 67: With the exception of R-1234ze(E) (Test 16), the compressor power values 

were within +/- 2.5% of the baseline. R-1234ze(E) had 4.3% lower power than the baseline. 

• Rows 69 and 70: The compressor run time for R-1234ze(E) (Test 16) was 20.0% higher than 

the baseline.

• Rows 79 and 80: The average cooling capacity for R-1234yf and R-1234ze were 5.1% and

5.3% lower, respectively

• Rows 80.1 and 80.2: The average COP for R-1234yf was 6.3% lower
Page 10

Table 4

Results at 23.9°C (75°F)/55% relative humidity ambient conditions, 

-5.6°C (22°F) bottle cooler setpoint

Row 0 Refrigerant

1 Test type

2 Test ID no.

4 Test cell temperature setpoint db °C 23.9 23.9 23.9 23.9 23.9

4.1 Test cell temperature setpoint wb °C 17.8 17.8 17.8 17.8 17.8

5 Test cell relative humidity setpoint, %

6 Bottle cooler setpoint °C -5.6 -5.6 -5.6 -5.6 -5.6

8 Completion date

9 Suction pressure kPa 189 205 209 132 175

10 Discharge pressure kPa 796 822 829 592 749

11 Refrigerant flow rate kg/hr 8.06 9.64 8.68 7.41 8.04

12 Difference %

13 Refrigerant pressure drop evaporator kPa 2.90 4.13 3.89 3.29 4.51

14 Refrigerant pressure drop condenser kPa 1.41 2.29 1.92 1.62 1.68

15 Refrigerant pressure drop flow meter kPa 27.16 26.36 22.04 22.67 24.36

16 Compressor suction temperature °C 9.5 10.8 14.9 12.4 13.1

17 Compressor discharge temperature °C 47.7 47.7 49.7 47.9 49.8

18 Evaporator outlet temperature °C -10.2 -10.4 -9.3 -10.4 -9.9

19 Condenser air inlet temperature °C 23.6 24.2 24.1 23.4 24.1

20 Condenser air outlet temperature °C 25.6 26.3 26.1 25.2 26.1

21 Condenser refrigerant inlet temperature °C 36.8 38.3 39.1 36.6 38.6

22 Condenser refrigerant outlet temp °C 28.9 30.0 29.4 28.2 29.2

23 Refrigerated air discharge temperature 5 cm from left wall °C -6.4 -6.5 -6.4 -6.6 -6.6

24 Refrigerated air discharge temperature center °C -6.5 -6.6 -6.4 -6.7 -6.6

25 Refrigerated air dischrage temperature 5 cm from right wall °C -6.7 -6.8 -6.6 -6.9 -6.8

26 Refrigerated air return temperature 5 cm from left wall °C -4.8 -4.8 -4.7 -5.0 -4.8

27 Refrigerated air return temperature center °C -4.3 -4.3 -4.2 -4.5 -4.3

28 Refrigerated air return temperature 5 cm from right wall °C -4.3 -4.2 -4.0 -4.3 -4.2

29 Test cell dry bulb (1 of 2) °C 23.9 24.5 24.3 23.8 24.1

30 Test cell dry bulb (2 of 2) °C 23.4 24.1 24.0 23.7 24.1

31 Test cell wet bulb °C 17.6 18.3 18.4 18.5 18.2

40 Test cell relative humidity %

50 Product simulator temperatures

51 Integrated average product simulator temperature °C -4.6 -4.6 -4.5 -4.7 -4.5

52 {CTS} Integrated coldest product simulator. temperature °C -5.5 -5.5 -5.4 -5.6 -5.6

54 {WTS} Integrated warmest product simulator temperature °C -4.0 -3.9 -3.7 -3.9 -3.8

59 Refrigerant charge g 322+/-7 322+/-7 322 +/-1 322 +/-1 322 +/-1

61 Supply voltage

66 Compressor power W

67 Difference %

69 Compressor run time, %

70 Difference %

71 Evaporator fan power W (checked once, not recorded 

continuously)

73 Evaporating temperature (avg. of dew and bubble ) °C -11.5 -11.8 -11.7 -12.6 -12.6

74 Condensing temperature (avg. of dew and bubble) °C 31.2 32.4 32.7 30.8 30.9

75 Superheat at compressor inlet °K 21.0 22.6 26.6 25.0 25.7

79 Average cooling capacity W* 372 352 359 319 348

80 Difference %

80.1 Average COP (W/W) 2.25 1.97 2.04 2.02 2.08

80.2 Difference % 0.0% -12.5% -9.5% -10.3% -7.8%

*Assumes saturated liquid at inlet of expansion device

60.6%

0%

0.0% 19.6%

53.9% 55.1%

165 178

0%

118

56.7% 60.0% 56.6%

168

1.4%

61.0%

18.1% 0.7%

71.6%

7.7% -8.2% -0.3%

-1.5% -9.0%

59.7%

8.0%

176 158

120

6.5%

55.1%

-4.4%

R-1234ze

ASHRAE

55

11/21/10 03/29/11

R-134a

ASHRAE

55

ASHRAE

55

10/07/10 03/06/11

R-1234yf

ASHRAE

55

OpteonTM 

XP10

ASHRAE

55

01/09/11

N13a

8 9 10 11 12

119 121 120

58 58 58 58 58

0% -5.5% -3.6% -14.3% -6.5%
Page 11

Table 5

Results at 26.7°C (80°F)/55% relative humidity ambient conditions, 

3.3°C (38°F) bottle cooler setpoint

Row 0 Refrigerant

1 Test type

2 Test ID no.

4 Test cell temperature setpoint db °C 26.7 26.7 26.7 26.7 26.7

4.1 Test cell temperature setpoint wb °C 20.1 20.1 20.1 20.1 20.1

5 Test cell relative humidity setpoint, %

6 Bottle cooler setpoint °C 3.3 3.3 3.3 3.3 3.3

8 Completion date

9 Suction pressure kPa 281 299 302 201 259

10 Discharge pressure kPa 766 783 792 612 727

11 Refrigerant flow rate kg/hr 6.88 7.90 7.39 7.04 7.06

12 Difference %

13 Refrigerant pressure drop evaporator kPa 1.58 1.68 1.85 3.46 3.09

14 Refrigerant pressure drop condenser kPa 1.43 1.59 1.87 1.26 1.77

15 Refrigerant pressure drop flow meter kPa 26.60 28.57 26.12 30.87 29.68

16 Compressor suction temperature °C 21.1 21.9 22.7 20.2 22.1

17 Compressor discharge temperature °C 44.7 44.8 46.2 44.4 46.0

18 Evaporator outlet temperature °C -0.6 1.2 1.4 -0.4 0.8

19 Condenser air inlet temperature °C 26.5 26.4 26.6 26.5 26.6

20 Condenser air outlet temperature °C 28.6 28.5 28.7 28.3 28.8

21 Condenser refrigerant inlet temperature °C 36.0 36.4 36.8 35.7 36.3

22 Condenser refrigerant outlet temp °C 30.7 30.6 30.9 30.5 30.6

23 Refrigerated air discharge temperature 5 cm from left wall °C 2.3 2.4 2.3 2.4 2.3

24 Refrigerated air discharge temperature center °C 2.4 2.5 2.5 2.5 2.5

25 Refrigerated air dischrage temperature 5 cm from right wall °C 2.2 2.3 2.3 2.3 2.2

26 Refrigerated air return temperature 5 cm from left wall °C 3.8 3.9 3.8 3.8 3.8

27 Refrigerated air return temperature center °C 4.1 4.2 4.2 4.2 4.2

28 Refrigerated air return temperature 5 cm from right wall °C 4.1 4.3 4.3 4.3 4.4

29 Test cell dry bulb (1 of 2) °C 26.8 26.6 26.7 26.8 26.8

30 Test cell dry bulb (2 of 2) °C 26.2 26.1 26.3 26.4 26.3

31 Test cell wet bulb °C 20.0 20.3 20.0 19.9 20.3

40 Test cell relative humidity %

50 Product simulator temperatures

51 Integrated average product simulator temperature °C 4.0 4.0 4.0 4.1 4.1

52 {CTS} Integrated coldest product simulator. temperature °C 3.3 3.3 3.3 3.4 3.4

54 {WTS} Integrated warmest product simulator temperature °C 4.5 4.6 4.6 4.6 4.7

59 Refrigerant charge g 322+/-7 322+/-7 322 +/-1 322 +/-1 322 +/-1

61 Supply voltage

66 Compressor power W

67 Difference %

69 Compressor run time, %

70 Difference %

71 Evaporator fan power W (checked once, not recorded 

continuously)

73 Evaporating temperature (avg. of dew and bubble ) °C -1.2 -1.3 -1.8 -1.9 -2.3

74 Condensing temperature (avg. of dew and bubble) °C 29.8 30.6 26.0 31.9 29.8

75 Superheat at compressor inlet °K 22.3 23.2 24.5 22.2 24.4

79 Average cooling capacity W* 328 312 336 311 321

80 Difference %

80.1 Average COP (W/W) 2.50 2.34 2.50 2.47 2.47

80.2 Difference % 0.0% -6.3% -0.1% -1.1% -1.2%

*Assumes saturated liquid at inlet of expansion device

119 121 121 121 120

46.8%

-4.3%

20.0%

41.1%

5.4%

132

0% 1.3%

133 135

2.5%

126 130

-1.1%

39.0%

0% -3.3%

37.7% 38.1%

-2.2%

53.3% 56.4% 54.1% 52.9% 54.9%

0% 14.8% 7.3% 2.3% 2.5%

ASHRAE ASHRAE

55 55

03/13/11 04/06/11

16 17

R134a R-1234yf OpteonTM 

XP10

55 55

R-1234ze

55

10/19/10 12/02/10 01/03/11

N13a

ASHRAE ASHRAE ASHRAE

13 14 15

58 58 58 58 58

0% -5.1% 2.4% -5.3% -2.3%
Page 12

Table 6 shows results at 26.7°C/55% relative humidity ambient conditions with the -5.6°C bottle 

cooler setpoint. Some main results in this table are:

• Rows 9 and 10: The suction and discharge pressures, 127 kPa and 644 kPa, respectively of 

R-1234ze(E) (Test 21) were considerably lower than the other refrigerants. 

• Rows 11 and 12: The mass flow rate of R-1234yf (Test 19) was 22.3% higher than the 

baseline.

• Rows 23 through 25: The discharge air temperatures were nearly identical for all tests. 

• Rows 66 and 67: The compressor power values were 5.8% higher, 6.3% higher, 4.8% lower 

and 2.0% lower for R-1234yf, XP10, R-1234ze(E), and N13a, respectively. 

• Rows 69 and 70: The compressor run time for R-1234ze(E) (Test 21) was 18.2% higher than 

the baseline.

• Rows 79 and 80: The average cooling capacity for R-1234ze and N13a were 12.9%, and 

5.6% lower, respectively

• Rows 80.1 and 80.2: The average COP for R-1234yf, XP10, and R-1234ze were 9.5%, 7.2%, 

and 8.6% lower, respectively

3.2 Full and half pull-down tests

Table 7 shows full pull-down results. Some main items in this table are:

• Rows 9 and 10: The suction and discharge pressures, 182 kPa and 789 kPa, respectively of 

R-1234ze(E) (Test 26) were considerably lower than the other refrigerants. 

• Rows 11 and 12: The mass flow rate of R-1234yf (Test 24) was 19.9% higher than the 

baseline.

• Rows 23 through 25: The discharge air temperatures were nearly identical for all tests. 

• Rows 66 and 67: The compressor power values were 4.8% higher, 2.4% higher, 11.2% lower 

and 2.9% lower for R-1234yf, XP10, R-1234ze(E), and N13a, respectively. 

• Rows 69 and 70: The compressor run times were within +/- 2.2% with the exception of R1234ze(E) (Test 26), which was 12.5% higher than the baseline.

• Rows 79 and 80: The average cooling capacity for R-1234yf, XP10, R-1234ze, and N13a 

were 6.2%, 6.0%, 9.9%, and 1.1% lower, respectively

• Rows 80.1 and 80.2: The average COP for R-1234yf and XP10 were 10.5% lower and 8.1%, 

respectively

• Rows 108 and 109: The amount of time until compressor started cycling was within +/- 5.2% 

with the exception of R-1234ze(E) (Test 26), which took 31.3% longer. 

The compressor was relatively undersized for use with R-1234ze(E). In the pull-down test, we 

saw a main disadvantage of an undersized compressor – longer pull-down time.
Page 13

Table 6

Results at 26.7°C (80°F)/55% relative humidity ambient conditions, 

-5.6°C (22°F) bottle cooler setpoint

Row 0 Refrigerant

1 Test type

2 Test ID no.

4 Test cell temperature setpoint db °C 26.7 26.7 26.7 26.7 26.7

4.1 Test cell temperature setpoint wb °C 20.1 20.1 20.1 20.1 20.1

5 Test cell relative humidity setpoint, %

6 Bottle cooler setpoint °C -5.6 -5.6 -5.6 -5.6 -5.6

8 Completion date

9 Suction pressure kPa 187 204 205 127 172

10 Discharge pressure kPa 836 863 894 644 795

11 Refrigerant flow rate kg/hr 8.19 10.01 9.29 7.80 8.35

12 Difference %

13 Refrigerant pressure drop evaporator kPa 3.67 4.42 3.86 3.13 4.37

14 Refrigerant pressure drop condenser kPa 1.59 2.52 2.23 1.84 1.97

15 Refrigerant pressure drop flow meter kPa 17.57 24.21 21.85 20.70 19.43

16 Compressor suction temperature °C 14.6 13.9 16.6 15.2 16.1

17 Compressor discharge temperature °C 52.5 52.3 54.1 53.6 53.6

18 Evaporator outlet temperature °C -10.6 -10.4 -9.7 -10.9 -10.0

19 Condenser air inlet temperature °C 26.1 26.2 26.3 26.0 26.2

20 Condenser air outlet temperature °C 28.2 28.3 28.4 27.9 28.4

21 Condenser refrigerant inlet temperature °C 41.0 41.9 42.9 41.5 42.3

22 Condenser refrigerant outlet temp °C 31.6 32.1 32.1 31.3 31.8

23 Refrigerated air discharge temperature 5 cm from left wall °C -6.4 -6.4 -6.4 -6.8 -6.5

24 Refrigerated air discharge temperature center °C -6.5 -6.5 -6.5 -6.9 -6.6

25 Refrigerated air dischrage temperature 5 cm from right wall °C -6.7 -6.8 -6.7 -7.2 -6.9

26 Refrigerated air return temperature 5 cm from left wall °C -4.6 -4.6 -4.6 -5.1 -4.7

27 Refrigerated air return temperature center °C -4.0 -4.1 -4.0 -4.5 -4.1

28 Refrigerated air return temperature 5 cm from right wall °C -4.0 -4.0 -3.9 -4.4 -4.0

29 Test cell dry bulb (1 of 2) °C 26.6 26.6 26.7 26.8 26.6

30 Test cell dry bulb (2 of 2) °C 26.1 26.2 26.3 26.5 26.4

31 Test cell wet bulb °C 20.0 20.3 20.1 21.3 20.3

40 Test cell relative humidity %

50 Product simulator temperatures

51 Integrated average product simulator temperature °C -4.3 -4.4 -4.3 -4.8 -4.4

52 {CTS} Integrated coldest product simulator. temperature °C -5.5 -5.4 -5.3 -5.7 -5.5

54 {WTS} Integrated warmest product simulator temperature °C -3.4 -3.5 -3.5 -3.9 -3.6

59 Refrigerant charge g 322+/-7 322+/-7 322 +/-1 322 +/-1 322 +/-1

61 Supply voltage

66 Compressor power W

67 Difference %

69 Compressor run time, %

70 Difference %

71 Evaporator fan power W (checked once, not recorded 

continuously)

73 Evaporating temperature (avg. of dew and bubble ) °C -11.7 -12.1 -12.2 -13.6 -13.0

74 Condensing temperature (avg. of dew and bubble) °C 32.9 34.2 35.6 33.7 33.0

75 Superheat at compressor inlet °K 26.2 26.1 28.8 28.8 29.1

79 Average cooling capacity W* 382 366 377 333 361

80 Difference %

80.1 Average COP (W/W) 2.11 1.91 1.96 1.93 2.03

80.2 Difference % 0.0% -9.5% -7.2% -8.6% -3.7%

*Assumes saturated liquid at inlet of expansion device

118 120 122 120 119

-0.5%

65.8%

6.3%

192 172

-4.8%

-5.9%

62.3% 78.2%

0% 18.2%

66.2%

-2.0%

177

0%

181 192

5.8%

62.6%

-5.5%

54.4% 56.4% 54.5% 61.4% 55.8%

0% 22.3% 13.5% -4.8% 2.0%

03/10/11 04/03/11

55 55

ASHRAE ASHRAE ASHRAE

R-1234ze N13a

18 19 21

ASHRAE ASHRAE

OpteonTM 

XP10

22

01/05/11

55 55 55

10/24/10 12/06/10

R134a R-1234yf

20

58 58 58 58 58

0% -4.2% -1.4% -12.9% -5.6%
Page 14

Table 7

Full pull-down test results

Row 0 Refrigerant

1 Test type

2 Test ID no.

4 Test cell temperature setpoint db °C 32.2 32.2 32.2 32.2 32.2

4.1 Test cell temperature setpoint wb °C 26.6 26.6 26.6 26.6 26.6

5 Test cell relative humidity setpoint, %

6 Bottle cooler setpoint °C 3.3 3.3 3.3 3.3 3.3

8 Completion date

9 Suction pressure kPa 251 271 268 182 238

10 Discharge pressure kPa 1043 1087 1081 789 979

11 Refrigerant flow rate kg/hr 9.96 11.94 10.80 9.77 10.40

12 Difference %

13 Refrigerant pressure drop evaporator kPa 2.64 2.46 3.23 4.00 4.00

14 Refrigerant pressure drop condenser kPa 2.12 2.45 2.36 2.26 2.15

15 Refrigerant pressure drop flow meter kPa 29.58 33.10 30.12 33.72 33.78

16 Compressor suction temperature °C 25.7 26.9 26.8 25.4 25.6

17 Compressor discharge temperature °C 63.3 64.1 65.2 60.2 63.1

18 Evaporator outlet temperature °C -0.6 -0.6 1.4 0.3 -0.2

19 Condenser air inlet temperature °C 33.3 34.2 33.3 32.3 33.1

20 Condenser air outlet temperature °C 35.7 36.9 35.8 34.7 35.7

21 Condenser refrigerant inlet temperature °C 51.9 53.4 52.8 49.4 50.9

22 Condenser refrigerant outlet temp °C 39.9 41.6 40.3 38.7 39.8

23 Refrigerated air discharge temperature 5 cm from left wall °C 2.4 2.5 2.6 3.0 2.7

24 Refrigerated air discharge temperature center °C 2.5 2.5 2.7 3.2 2.8

25 Refrigerated air dischrage temperature 5 cm from right wall °C 2.2 2.3 2.3 2.9 2.5

26 Refrigerated air return temperature 5 cm from left wall °C 4.7 5.0 5.0 5.4 5.1

27 Refrigerated air return temperature center °C 5.8 5.9 6.0 6.5 6.0

28 Refrigerated air return temperature 5 cm from right wall °C 5.6 5.9 5.8 6.3 6.1

29 Test cell dry bulb (1 of 2) °C 34.0 35.1 33.9 33.2 33.8

30 Test cell dry bulb (2 of 2) °C 33.2 34.4 33.3 32.6 33.2

31 Test cell wet bulb °C 26.7 26.2 27.0 26.6 26.8

40 Test cell relative humidity %

50 Product simulator temperatures

51 Integrated average product simulator temperature °C 7.6 7.8 7.8 8.2 7.9

52 {CTS} Integrated coldest product simulator. temperature °C 2.6 2.6 2.5 2.7 2.7

54 {WTS} Integrated warmest product simulator temperature °C 32.9 32.8 32.5 32.7 32.8

59 Refrigerant charge g 322+/-7 322+/-7 322 +/-1 322 +/-1 322 +/-1

61 Supply voltage

66 Compressor power W

67 Difference %

69 Compressor run time, %

70 Difference %

71 Evaporator fan power W (checked once, not recorded 

continuously)

73 Evaporating temperature (avg. of dew and bubble ) °C -4.2 -4.2 -5.1 -4.7 -4.6

74 Condensing temperature (avg. of dew and bubble) °C 40.9 43.3 43.1 40.9 40.7

75 Superheat at compressor inlet °K 29.9 31.1 31.9 30.1 30.2

79 Average cooling capacity W* 455 427 428 410 451

80 Difference %

80.1 Average COP (W/W) 2.13 1.91 1.96 2.16 2.17

80.2 Difference % 0.0% -10.5% -8.1% 1.4% 1.9%

*Assumes saturated liquid at inlet of expansion device

100 Maximum compressor discharge temperature** °C 88.8 85.5 87.1 77.5 84.5

101 Maximum compressor suction temperature** °C 37.1 36.0 36.7 36.0 36.3

108 Amount of time until compressor cycling starts minutes

109 Difference %

**Measured from start of test until the compressor first cycles off

72 hour minimum thermal soak time for pulldown and half pulldown tests

119 121 121 120 121

207

-11.2% -2.9%

59.7% 61.9%

0% 2.4%

219

-2.2%

61.0%

1.5%

31.3%

58

0%

291 291

-6.2%

0% 0.0%

305

4.8%

306 382

5.2%

190

68.7%

12.5%

224

4.8%

61.0%

0.0%

214

56.4% 49.6% 58.6% 59.6% 58.0%

0% 19.9% 8.4% -1.9% 4.4%

R-1234ze N13a

Pulldown Pulldown Pulldown Pulldown Pulldown

OpteonTM 

XP10

65 65 65

12/14/10 01/18/11 03/16/11 05/04/11

65 65

23 24 25 26 27

R-1234yf

10/28/10

R134a

58 58 58 58

0% -6.0% -9.9% -1.1%
Page 15

Table 8 shows half pull-down results. Some main results in this table are:

• Rows 9 and 10: The suction and discharge pressures, 184 kPa and 756 kPa, respectively of 

R-1234ze(E) (Test 31) were considerably lower than the other refrigerants. 

• Rows 11 and 12: The mass flow rate of R-1234yf (Test 29) was 17.4% higher than the 

baseline.

• Rows 23 through 25: The discharge air temperatures were nearly identical for all tests. 

• Rows 66 and 67: The compressor power values were 2.7% higher, 4.2% higher, 5.2% lower 

and 0.5% lower for R-1234yf, XP10, R-1234ze(E), and N13a, respectively. 

• Rows 69 and 70: The compressor run times were 0.8% higher, 8.2% higher, 20.0% higher 

and 11.3% higher for R-1234yf, XP10, R-1234ze(E), and N13a, respectively. 

• Rows 79 and 80: The average cooling capacity for R-1234yf, XP10, R-1234ze, and N13a 

were 6.8%, 6.9%, 7.8%, and 6.5% lower, respectively

• Rows 80.1 and 80.2: The average COP for R-1234yf, XP10, and N13a were 9.3%, 10.7%, 

and 6.1% lower, respectively

• Rows 108 and 109: The amount of time until the compressor cycling started were 10% lower, 

3.8% lower, 40.8% higher and 50.8% higher for R-1234yf, XP10, R-1234ze(E), and N13a, 

respectively. The time until compressor cycling started for the N13a blend seems 

inconsistent with the other values. Given the other results, we expected this value to be closer 

to the baseline. The cause of this unexpected result is not known.
Page 16

Table 8

Half pull-down test results

Row 0 Refrigerant

1 Test type

2 Test ID no.

4 Test cell temperature setpoint db °C 32.2 32.2 32.2 32.2 32.2

4.1 Test cell temperature setpoint wb °C 26.6 26.6 26.6 26.6 26.6

5 Test cell relative humidity setpoint, %

6 Bottle cooler setpoint °C 3.3 3.3 3.3 3.3 3.3

8 Completion date

9 Suction pressure kPa 258 276 263 184 229

10 Discharge pressure kPa 949 966 976 756 900

11 Refrigerant flow rate kg/hr 8.54 10.02 9.10 8.70 8.67

12 Difference %

13 Refrigerant pressure drop evaporator kPa 2.86 2.30 3.32 4.44 0.63

14 Refrigerant pressure drop condenser kPa 1.97 1.85 2.22 2.00 0.34

15 Refrigerant pressure drop flow meter kPa 25.39 32.02 26.58 29.41 4.16

16 Compressor suction temperature °C 25.0 25.0 25.1 24.9 25.1

17 Compressor discharge temperature °C 57.8 57.5 60.4 57.4 59.7

18 Evaporator outlet temperature °C -0.8 0.3 1.7 -0.9 1.2

19 Condenser air inlet temperature °C 32.1 32.0 31.5 32.3 89.5

20 Condenser air outlet temperature °C 34.4 34.5 33.9 34.6 93.6

21 Condenser refrigerant inlet temperature °C 47.1 47.1 48.1 46.8 117.4

22 Condenser refrigerant outlet temp °C 37.7 38.0 37.1 38.0 99.2

23 Refrigerated air discharge temperature 5 cm from left wall °C 2.0 1.9 2.2 2.1 2.2

24 Refrigerated air discharge temperature center °C 2.0 2.0 2.4 2.1 2.3

25 Refrigerated air dischrage temperature 5 cm from right wall °C 1.8 1.7 1.9 1.9 1.9

26 Refrigerated air return temperature 5 cm from left wall °C 3.9 3.8 4.0 4.0 39.5

27 Refrigerated air return temperature center °C 4.3 4.3 4.5 4.5 40.3

28 Refrigerated air return temperature 5 cm from right wall °C 4.5 4.4 4.7 4.7 40.6

29 Test cell dry bulb (1 of 2) °C 32.4 32.5 32.3 33.2 90.8

30 Test cell dry bulb (2 of 2) °C 32.0 31.9 31.8 32.6 89.8

31 Test cell wet bulb °C 26.5 25.8 27.1 26.7 79.0

40 Test cell relative humidity %

50 Product simulator temperatures

51 Integrated average product simulator temperature °C 5.6 5.5 5.7 5.7 5.8

52 {CTS} Integrated coldest product simulator. temperature °C 3.2 3.1 3.3 3.2 37.8

54 {WTS} Integrated warmest product simulator temperature °C 32.3 32.4 32.6 32.7 90.8

59 Refrigerant charge g 322+/-7 322+/-7 322 +/-1 322 +/-1 322 +/-1

61 Supply voltage

66 Compressor power W

67 Difference %

69 Compressor run time, %

70 Difference %

71 Evaporator fan power W (checked once, not recorded 

continuously)

73 Evaporating temperature (avg. of dew and bubble ) °C -3.4 -3.6 -5.6 -4.2 -5.7

74 Condensing temperature (avg. of dew and bubble) °C 37.4 38.6 39.0 39.5 37.5

75 Superheat at compressor inlet °K 28.4 28.6 30.7 29.1 30.7

79 Average cooling capacity W* 401 373 373 370 375

80 Difference %

80.1 Average COP (W/W) 2.24 2.03 2.00 2.18 2.10

80.2 Difference % 0.0% -9.3% -10.7% -2.7% -6.1%

*Assumes saturated liquid at inlet of expansion device

100 Maximum compressor discharge temperature** °C 81.1 79.7 80.2 73.9 77.7

101 Maximum compressor suction temperature** °C 32.5 32.5 32.3 33.6 32.0

108 Amount of time until compressor cycling starts minutes

109 Difference %

**Measured from start of test until the compressor first cycles off

72 hour minimum thermal soak time for pulldown and half pulldown tests

119 121 122 120 120

0% -10.0% -3.8% 40.8% 50.8%

130

178

-0.5%

57.5%

11.3%

117 125 183 196

55.9%

8.2%

184

2.7%

52.1%

0.8%

179

0%

51.7%

0%

170

-5.2%

62.0%

20.0%

187

4.2%

62.8% 58.8% 67.4% 60.2% 59.5%

1.6%

R134a

HalfPulldown

N13a

HalfPulldown

65

12/21/10 02/09/11

R-1234ze

HalfPulldown

0% 17.4% 6.6% 1.9%

R-1234yf

HalfPulldown

65 65

28 29

03/21/11

OpteonTM 

XP10

HalfPulldown

65 645

30 31

11/08/10 04/19/11

32

58 58 58 58 58

0% -6.8% -6.9% -7.8% -6.5%
Page 17

4. Discussion and Conclusions

4.1 ASHRAE 72 Tests

All things being equal, we consider the COP values to be a main result for this series of tests. In 

nearly all cases, the COP of the test refrigerants was lower than the baseline.

As explained earlier, the same charge mass was used for each refrigerant. The test unit was a 

critically charged capillary tube system, and as is well known, critically charged systems are 

sensitive to the charge amount. Some of the test refrigerants may have had better performance if 

the charge were adjusted. For example, in Table 6, Row 75, it can be seen that the superheat at 

the compressor was 29.1°K for N13a versus 26.2°K for R134a. In this example, the N13a may 

have had a higher COP value if more refrigerant were used.

4.2 Full and half pull-down tests

With the full and half pull-down tests, the amount of time until the compressor cycling started is 

a main result. Because R-1234ze(E) has lower density, it required longer pull-down times. The 

pull-down times could be shorter if a larger displacement compressor were used.